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Type 1 diabetes (T1D) is a chronic condition characterized by glucose fluctuations. Laboratory studies suggest that cognition is reduced when glucose is very low (hypoglycemia) and very high (hyperglycemia). Until recently, technological limitations prevented researchers from understanding how naturally-occurring glucose fluctuations impact cognitive fluctuations. This study leveraged advances in continuous glucose monitoring (CGM) and cognitive ecological momentary assessment (EMA) to characterize dynamic, within-person associations between glucose and cognition in naturalistic environments. Using CGM and EMA, we obtained intensive longitudinal measurements of glucose and cognition (processing speed, sustained attention) in 200 adults with T1D. First, we used hierarchical Bayesian modeling to estimate dynamic, within-person associations between glucose and cognition. Consistent with laboratory studies, we hypothesized that cognitive performance would be reduced at low and high glucose, reflecting cognitive vulnerability to glucose fluctuations. Second, we used data-driven lasso regression to identify clinical characteristics that predicted individual differences in cognitive vulnerability to glucose fluctuations. Large glucose fluctuations were associated with slower and less accurate processing speed, although slight glucose elevations (relative to person-level means) were associated with faster processing speed. Glucose fluctuations were not related to sustained attention. Seven clinical characteristics predicted individual differences in cognitive vulnerability to glucose fluctuations: age, time in hypoglycemia, lifetime severe hypoglycemic events, microvascular complications, glucose variability, fatigue, and neck circumference. Results establish the impact of glucose on processing speed in naturalistic environments, suggest that minimizing glucose fluctuations is important for optimizing processing speed, and identify several clinical characteristics that may exacerbate cognitive vulnerability to glucose fluctuations. [ABSTRACT FROM AUTHOR]

Summary: The increased risk for fractures in type 2 diabetes mellitus (T2DM) despite higher average bone density is unexplained. This study assessed trabecular bone quality in T2DM using the trabecular bone score (TBS). The salient findings are that TBS is decreased in T2DM and low TBS associates with worse glycemic control. Introduction: Type 2 diabetes mellitus is a risk factor for osteoporotic fractures despite high average bone mineral density (BMD). The aim of this study was to compare BMD with a noninvasive assessment of trabecular microarchitecture, TBS, in women with T2DM. Methods: In a cross-sectional study, trabecular microarchitecture was examined in 57 women with T2DM and 43 women without diabetes, ages 30 to 90 years. Lumbar spine BMD was measured by dual-emission x-ray absorptiometry (DXA), and TBS was calculated by examining pixel variations within the DXA images utilizing TBS iNsight software. Results: Mean TBS was lower in T2DM (1.228 ± 0.140 vs. 1.298 ± 0.132, p = 0.013), irrespective of age. Mean BMD was higher in T2DM (1.150 ± 0.172 vs. 1.051 ± 0.125, p = 0.001). Within the T2DM group, TBS was higher (1.254 ± 0.148) in subjects with good glycemic control (A1c ≤ 7.5 %) compared to those (1.166 ± 0.094; p = 0.01) with poor glycemic control (A1c > 7.5 %). Conclusion: In T2DM, TBS is lower and associated with poor glycemic control. Abnormal trabecular microarchitecture may help explain the paradox of increased fractures at a higher BMD in T2DM. Further studies are needed to better understand the relationship between glycemic control and trabecular bone quality. [ABSTRACT FROM AUTHOR]

Objectives: To examine whether improved diabetes control is related to better cognitive outcomes. Design: Randomized control trial. Setting: A randomized trial of telemedicine vs. usual care in elderly persons with type 2 diabetes. Participants: Participants were 2169 persons 55 years and older with type 2 diabetes from New York City and Upstate New York. Intervention: The diabetes case management intervention was implemented by a diabetes nurse, via a telemedicine unit in the participant's home, and in coordination with the primary care physician. Measurements: Hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and low density lipoprotein cholesterol (LDL), were measured at a baseline visit and at up to 5 annual follow-up visits. Global cognition was measured at those visits with the Comprehensive Assessment and Referral Evaluation (CARE). Result: In mixed models the intervention was related to slower global cognitive decline in the intervention group (p = 0.01). Improvements in HbA1c (p = 0.03), but not SBP or LDL, mediated the effect of the intervention on cognitive decline. Conclusion: Improved diabetes control in the elderly following existing guidelines through a telemedicine intervention was associated with less global cognitive decline. The main mediator of this effect seemed to be improvements in HbA1c. [ABSTRACT FROM AUTHOR]

The aim of the study is to determine the effects of short-term high-intensity exercise on arterial function and glucose tolerance in obese individuals with and without the metabolic syndrome (MetSyn). Obese men and women (BMI > 30 kg/m(2); 39-60 years) with and without MetSyn (MetSyn, n = 13; Non-MetSyn, n = 13) participated in exercise training consisting of ten consecutive days of treadmill walking for 1 h/day at 70-75% of peak aerobic capacity. Changes in aerobic capacity, flow-mediated dilation (FMD), and arterial stiffness using central and peripheral pulse wave velocity (PWV) measurements were assessed pre- and post-training. These measurements were obtained fasting and 1-h post-test meal while the subjects were hyperglycemic. Aerobic capacity improved for both groups [Non-MetSyn 24.0 +/- 1.6 vs. 25.1 +/- 1.5 mL/(kg min); MetSyn 25.2 +/- 1.8 vs. 26.2 +/- 1.7 mL/(kg min), P < 0.05]. There was no change in body weight. FMD decreased by ~20% (P < 0.05) for both groups during acute hyperglycemia (MetSyn, n = 11; Non-MetSyn, n = 10), while hyperglycemia increased central PWV and not peripheral PWV. Exercise training did not change FMD in the fasted or challenged state. Central and peripheral PWV were not altered with training for either group (MetSyn, n = 13; Non-MetSyn, n = 13). A 10-day high-intensity exercise program in obese individuals improved aerobic capacity and glucose tolerance but no change in arterial function was observed. Acute hyperglycemia had a deleterious effect on arterial function, suggesting that persons with impaired glucose homeostasis may experience more opportunities for attenuated arterial function on a daily basis which could contribute to increased cardiovascular risk. [ABSTRACT FROM AUTHOR]

Objective:To examine the responsiveness of cardiac autonomic function and baroreflex sensitivity (BRS) to exercise training in obese individuals without (OB) and with type 2 diabetes (ObT2D).Design:Subjects were tested in the supine position and in response to a sympathetic challenge before and after a 16-week aerobic training program. All testing was conducted in the morning following a 12-h fast.Subjects:A total of 34 OB and 22 ObT2D men and women (40–60 years of age) were studied.Measurements:Heart rate variability (HRV) was measured at rest via continuous ECG (spectral analysis with the autoregressive approach) and in response to upright tilt. The dynamics of heart rate complexity were analyzed with sample entropy and Lempel–Ziv entropy, and BRS was determined via the sequence technique. Subjects were aerobically trained 4 times per week for 30–45 min for 16 weeks.Results:Resting HR decreased and total power (lnTP, ms2) of HRV increased in response to exercise training (P<0.05). High frequency power (lnHF) increased in OB subjects but not in OBT2D, and no changes occurred in ln low frequency/HF power with training. Upright tilt decreased lnTP and lnHF and increased LF/HF (P<0.01) but there were no group differences in the magnitude of these changes nor were they altered with training in either group. Tilt also decreased complexity (sample entropy and Lempel–Ziv entropy; P<0.001), but there was no group or training effect on complexity. BRS decreased with upright tilt (P<0.01) but did not change with training. Compared to OB subjects the ObT2D had less tilt-induced changes in BRS.Conclusion:Exercise training improved HRV and parasympathetic modulation (lnHF) in OB subjects but not in ObT2D, indicating plasticity in the autonomic nervous system in response to this weight-neutral exercise program only in the absence of diabetes. HR complexity and BRS were not altered by 16 weeks of training in either OB or ObT2D individuals. [ABSTRACT FROM AUTHOR]

We examined the risk of childhood cancer (<20 years) among 105 950 offspring born in 1921-1984 to US radiologic technologist (USRT) cohort members. Parental occupational in utero and preconception ionising radiation (IR) testis or ovary doses were estimated from work history data, badge dose data, and literature doses (the latter doses before 1960). Female and male RTs reported a total of 111 and 34 haematopoietic malignancies and 115 and 34 solid tumours, respectively, in their offspring. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression. Leukaemia (n=63) and solid tumours (n=115) in offspring were not associated with maternal in utero or preconception radiation exposure. Risks for lymphoma (n=44) in those with estimated doses of <0.2, 0.2-1.0, and >1.0 mGy vs no exposure were non-significantly elevated with HRs of 2.3, 1.8, and 2.7. Paternal preconception exposure to estimated cumulative doses above the 95th percentile (82 mGy, n=6 cases) was associated with a non-significant risk of childhood cancer of 1.8 (95% CI 0.7-4.6). In conclusion, we found no convincing evidence of an increased risk of childhood cancer in the offspring of RTs in association with parental occupational radiation exposure. [ABSTRACT FROM AUTHOR]